Manchester United’s entire season is on the line in the Europa League final

After a long and grueling season filled with disappointment, underperformance, injury and doubt, it all comes down to one game for Manchester United. One game and this whole season could flip-flop one direction or the other. For such a lengthy and complicated campaign, it's a refreshingly simple conclusion:

Win and this season's a success. Lose and the whole thing was a wash, a failure of epic proportions.

For a club like Manchester United, winning is the only acceptable result. They're England's biggest team, one of the most successful in European history, and they're the fifth most valuable sports franchise in the entire world.

For the last few years though, United have been anything but successful, and this Premier League campaign's sixth place finish is the latest in a string of domestic failures that the Red Devils just can't seem to break.

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Despite hiring Jose Mourinho as manager, breaking the world transfer record and spending more money than just about every other team in England, they still picked up the fewest wins and most draws they've ever accrued in a Premier League season. Over the course of this year, United managed just 54 goals in the league. They were outscored by every single team in the top seven, and outgunned by a full 31 goals by champions Chelsea.

United haven't been in Champions League since the 2013/14 season. It was the product of their only top four finish since Sir Alex Ferguson retired after the 2013 Premier League win. The Red Devils are on their third manager since Ferguson's retirement, and they've spent over a half billion on transfers since the legendary Scot decided to throw his last boot. The grand total of all that output? Zero league titles.

In his debut season, Mourinho led his team to a worse finish than Louis Van Gaal managed last year, despite adding the world class talents of Paul Pogba, Zlatan Ibrahimovic, Henrikh Mkhitaryan and Eric Bailly to the United ranks. No team missed more big chances than United and only two teams hit the woodwork more. Ibrahimovic was the only United player to score in double figures, with Juan Mata's paltry six goals the closest to his mark of 17.

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For long stretches this year, Manchester United have been distinctly unpalatable. They lacked a distinctive style of play, and end product was ugly and ineffective . Too often they've reeked of the worst Mourinho qualities: negative, defensive football with little invention or inspiration. If not for some individual moments of magic, United would have fared even worse.

At times United were legitimately terrible. On the basis of their league form, they didn't deserve Champions League spot, and with the amount of quality in their team and the amount of money spent to assemble it, it's hard to argue that fans shouldn't be upset with the results on offer.

Should United fail to beat Ajax in the Europa League final, this season will unquestionably be labeled a failure. Maybe even a disaster, seeing as Mourinho and the money spent brought all new sky high expectations, not to mention a clause in their adidas contract that could see them lose out on tens of millions of pounds should they not qualify for the Champions League.

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In spite of how awful things can look on the surface, it hasn't all been bad for United.

They've won two trophies already, picking up the Community Shield as well as the EFL Cup trophy. They were racked with injury this season, they weren't always as awful as the sixth-placed finish and the aforementioned damning statistics would indicate, and there's clear evidence of a solid core to build on for next year.

Some of their wins were vintage, old school flowing United with stylish passing, classy finishes and the promise of something exciting to hope for with better quality players in the team. There's reason for optimism in the United camp. Player recruitment won't be an issue with Champions League soccer on offer, and the Red Devils will be able to pull from the highest echelon of players if they can secure a berth in world soccer's elite competition.

Two trophies and a spot in the Champions League? That's impressive, without any qualifiers. And with the Red Devils on the rise, that's a smashing success.

But it all depends on beating Ajax.

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But it all depends on beating Ajax.

Every single one of United's eggs now lie in one basket. A bad 90 minutes against the young Dutchmen on Wednesday, and they'll be back in Europa League once more to restart the same dreary cycle they underwent this season.

A loss, and this entire season was trash. It goes straight down the drain. Mourinho's legacy and ability will be further called into question. Pogba will have to change his zip code to "under the bus", and worst of all, United will still be an afterthought or punchline -- a once powerful team that can't even play with the continent's best, let alone beat them.

If United lose to Ajax, they'll be the laughingstock of the entire soccer world. They're the team that tanked in the Premier League to concentrate on Europa League... and lost. The memes might just break Twitter. Early indications from the meme markets show that "Ajax in the Europa" has a strong chance of usurping "3-1 in the Finals" for worst slander on the internets.

So are they back on their way to the mountaintop or abject failures worthy of ridicule? One match will decide it.